The Effect of the Reactor Type on the Selectivity of Thermal Reactions of p-Xylene in Temperature Gradient Systems

Article abstract of DOI:10.1246/bcsj.64.1000

Thermal reactions of p-xylene were investigated in two kinds of reactors, batch type and flow type, with a large temperature gradient.Excellent differences of the resulting products were observed between these two types of reactors.As for a batch type reactor, 4,4'-dimethylbibenzyl was produced in a high yield with <2.2>paracyclophane and toluene as by-products, and as for a flow type reactor, toluene was obtained as a major product with a low selectivity of 4,4'-dimethylbibenzyl, respectively.These results were different from those of the conventional fast flow pyrolysis method in which <2.2>paracyclophane or poly(3,6-dimethylene-1,4-cyclohexadiene) was formed as a major product.These differences can be accounted for by the partial separation of a reaction mixture caused by the thermal diffusion effect, which arises when the mixture is subject to a temperature gradient.